Note: Descriptions are shown in the official language in which they were submitted.
International Application Number: IB2015054746
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1
MANAGEMENT OF WIRELESS DEVICES IN LIMITED RADIO COVERAGE
CLAIM OF PRIORITY
This application claims the benefit of priority to U.S. Provisional
Application
No. 62/016,558, filed on June 24, 2014, and to U.S. Provisional Application
No.
62/107,847, filed on January 26, 2015.
TECHNICAL FIELD
The present disclosure relates to radio transmission and reception of a
network
and a wireless device and, more particularly, to techniques for enhancing a
radio
coverage based on an exchange of radio condition information between a network
and a
wireless device for repeating data transmissions on a radio interface between
the
network and the wireless device.
BACKGROUND
The following abbreviations and terms are herewith defined, at least some of
which are referred to within the following description of the present
disclosure.
3C1PP 3rd-Generation Partnership Project
AGCH Access Grant Channel
AS1C Application Specific Integrated Circuit
BCCH Broadcast Control Channel
BSC Base Station Controller
BSS Base Station Subsystem
CC Coverage Class
CN Core Network
DSP Digital Signal Processor
eDRX Extended Discontinuous Receive
EC-GSM Extended Coverage-Global System for Mobile Communications
EDGE Enhanced Data rates for GSM Evolution
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EGPRS Enhanced General Packet Radio Service
eNB evolved Node B
E-UTRA Evolved Universal Terrestrial Radio Access
FCCH Frequency Correction Channel
GSM Global System for Mobile Communications
GERAN GSM/EDGE Radio Access Network
IMSI International Mobile Subscriber Identity
IoT Internet of Things
LLC Logical Link Control
MME Mobile Management Entity
MTC Machine Type Communications
NAS Non-Access Stratum
LTE Long-Term Evolution
PACCH Packet Associated Control Channel
PDN Packet Data Network
PDTCH Packet Data Traffic Channels
PDU Protocol Data Unit
RACH Random Access Channel
RAN Radio Access Node
RAT Radio Access Technology
RAU Routing Area Update
RCC Radio Coverage Category
RLC Radio Link Control
RNC Radio Network Controller
RRC Radio Resource Control
SCH Synchronization Channel
SGSN Serving GPRS Support Node
SI System Information
TLLI Temporary Logical Link Identifier
UE User Equipment
UL Uplink
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UMTS Universal Mobile Telecommunications System
WCDMA Wideband Code Division Multiple Access
WiMAX Worldwide Interoperability for Microwave Access
The anticipated ubiquitous deployment of wireless devices used for what is
known as Machine-Type-Communication (MTC) will result in wireless devices
being
placed outside the typical radio coverage of the existing radio networks,
e.g., in.
basements and similar locations. One way to improve the radio coverage is by
expanding the radio access network infrastructure, such as by adding
additional Radio
Base Station (RBS) equipment. This, however, may very quickly result in an
unreasonable investment effort and may not be acceptable to operators.
An alternative approach to adding additional equipment is to keep the existing
radio access network infrastructure unchanged but instead improve the radio
coverage
through novel radio transmission and reception techniques as well as new Radio
Resource Management algorithms. The latter approach is currently being
discussed
in the wireless industry and is a subject for a standardization effort, for
example, in
the 3rd-Generation Partnership Project (3GPP) as described in the 3GPP TR
36.824
V11Ø0 Technical Report, entitled "Evolved Universal Terrestrial Radio Access
(E-
UTRA); LTE coverage enhancements" and the 3GPP TSG-GERAN Meeting #62
Work Item Description GP-140421, entitled "New Study Item on Cellular System
Support for Ultra Low Complexity and Low Throughput Internet of Things."
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While there are many techniques that can be used to enhance the radio
coverage, one technique is to enhance the radio coverage through the use of
repeated
transmissions. The repeated transmissions technique is currently being
considered in
the context of the related standardization work in 3GPP TSG RAN, as described
in
the above-referenced 3GPP TR 36.824 V11Ø0 Technical Report, entitled
"Evolved
Universal Terrestrial Radio Access (E-UTRA); LTE coverage enhancements" as
well
as in 3GPP TSG GERAN as described in the 3GPP TR 45.820 V1.3.0 Technical
Report, entitled "Cellular System Support for Ultra Low Complexity and Low
Throughput Internet of Things".
A problem seen with the existing solutions associated with the repeated
transmissions technique described in the above-referenced Technical Reports is
that
neither the wireless device nor the network, in this case, the Radio Access
Network
(RAN) node responsible for the repeated transmissions (e.g., the evolved Node
B
(eNB) in Long Term Evolution (LTE), the Radio Network Controller (RNC) in 3G,
or
the Base Station Controller (B SC) in 2G), is aware of the Radio Coverage
Category
(RCC) applicable when starting up a new uplink or downlink data transmission
for a
wireless device. This may, in a large degree, result in either too few or too
many
repeated transmissions during the initial phase of the data transmissions with
the
wireless device (e.g., a period of time during which wireless device specific
RCC
information is not known by the RAN node). For example, too few repeated
transmissions may be initially applied to the transmissions, resulting in a
failed data
transmission, due to an erroneous initial estimate in the number of repeated
transmissions needed. This may then be followed by another set of repeated
transmissions based on a better understanding of the needed number of repeated
transmissions (e.g., derived from the failed data transmission) but still
resulting in
inefficient usage of the scarce radio resources. Alternatively, too many
repeated
transmissions may be initially applied to the transmissions, resulting in the
inefficient
usage of the scarce radio resources, adding interference to the network, and
consuming too much energy, etcetera.
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Given that a large portion of the applications associated with MTC (including
Internet of Things (101)) will be predominantly used for transfer of small
amounts of
a data (e.g., electricity meter data, temperature sensor data, etc.), an
improved
mechanism for accurately determining the number of needed repeated
transmissions
5 to and/or
from a wireless device would be a veiy valuable if not a critical requirement
to satisfy during the initial phase of downlink or uplink data transmission
between the
RAN node and the wireless device. This need and other needs are addressed by
the
present disclosure.
US 2004/0098761 Al discloses a method and apparatus for enhancing coverage
of Machine Type Communication (MTC) devices. In one embodiment, a MTC device
(wireless transmit/receive unit) may provide an Evolved Node B (eNB)
information
regarding coverage limitation, which may include one or more of the Physical
Random
Access Channel (PRACH) preamble transmit power, measured Reference Signal
Received Power (RSRP)/Reference Signal Received Quality (RSRQ) used for
suitable
cell selection criteria, number of preamble repetition and retransmissions or
number of
Physical Downlink Control Channel (PDCCH) and Physical Downlink Shared Channel
(PDSCH) repetitions needed for Random Access Reception (BAR) reception.
SUMMARY
A wireless device, a RAN node, a CN node, and various methods for addressing
at least the aforementioned need are described in the independent claims.
Advantageous embodiments of the wireless device, the RAN node, the CN node,
and
the various methods are further described in the dependent claims.
In one aspect, the present disclosure provides a wireless device configured to
communicate with a RAN node and a CN node. The wireless device comprises a
processor and a memoly that stores processor-executable instructions, wherein
the
processor interfaces with the memory to execute the processor-executable
instructions,
whereby the wireless device is operable to perform a first receive operation,
an estimate
operation, a map operation, a transmit operation, and a second receive
operation. In the
first receive operation, the wireless device is operable to receive, from the
RAN node,
control channels. In the estimate operation, the wireless device is operable
to estimate
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5a
a downlink radio condition based on a signal quality of the received control
channels.
In the map operation, the wireless device is operable to map the estimated
downlink
radio condition to one of a plurality of downlink Radio Coverage Category
(RCC)
values. In the transmit operation, the wireless device is operable to
transmit, to the
RAN node, a first message including the one downlink RCC value. In the second
receive operation, the wireless device is operable to receive, from the RAN
node, a
second message having a number of repeated downlink transmissions based on the
one
downlink RCC value. The wireless device configured to operate in this manner
will
address the need in the state-of-the-art by effectively using scarce radio
resources,
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reducing interference to the network, and reducing the consumption of the
wireless
device's battery power, etcetera, during the initial phase of data
transmission.
In another aspect, the present disclosure provides a method in a wireless
device configured to communicate with a RAN node and a CN node. The method
comprises a first receive step, an estimate step, a map step, a transmit step,
and a
second receive step. In the first receive step, control channels are received
from the
RAN node. In the estimate step, a downlink radio condition is estimated based
on a
signal quality of the received control channels. In the map step, the
estimated downlink
radio condition is mapped to one of a plurality of downlink Radio Coverage
Category
(RCC) values. In the transmit step, a first message is transmitted to the RAN
node,
wherein the first message includes the one downlink RCC value. In the second
receive
step, a second message is received from the RAN node, wherein the second
message
has a number of repeated downlink transmissions based on the one downlink RCC
value. The method will address the need in the state-of-the-art by effectively
using
scarce radio resources, reducing interference to the network, and reducing the
consumption of the wireless device's battery power, etcetera, during the
initial phase of
data transmission.
In yet another aspect, the present disclosure provides a RAN node configured
to communicate with one or more wireless devices and a CN node. The RAN node
comprises a processor and at least one memory that stores processor-executable
instructions, wherein the processor interfaces with the at least one memory to
execute
the processor-executable instructions, whereby the RAN node is operable to
perform a
first transmit operation, a receive operation, and a second transmit
operation. In the
first transmit operation, the RAN node is operable to transmit, to the one or
more
wireless devices, control channels. In the receive operation, the RAN node is
operable
to receive, from one of the wireless devices, a first message including a
first downlink
Radio Coverage Category (RCC) value. In the second transmit operation, the RAN
node is operable to transmit, to the one wireless device, a second message
that is
repeated according to the first downlink RCC value included in the first
message
received from the one wireless device. The RAN node configured to operate in
this
manner will address the need in the state-of-the-art by effectively using
scarce radio
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resources, reducing interference to the network, and reducing the consumption
of the
wireless device's battery power, etcetera, during the initial phase of data
transmission.
In yet another aspect, the present disclosure provides a method in a RAN node
configured to communicate with one or more wireless devices and a CN node. The
method comprises a first transmit step, a receive step, and a second transmit
step. In
the first transmit step, control channels are transmitted to the one or more
wireless
devices. In the receive step, a first message is received from one of the
wireless
devices, wherein the first message includes a first downlink Radio Coverage
Category
(RCC) value. In the second transmit step, a second message is transmitted to
the one
wireless device, wherein the second message is repeated according to the first
downlink
RCC value included in the first message received from the one wireless device.
The
method will address the need in the state-of-the-art by effectively using
scarce radio
resources, reducing interference to the network, and reducing the consumption
of the
wireless device's battery power, etcetera, during the initial phase of data
transmission.
In still yet another aspect, the present disclosure provides a CN node
configured
to communicate with a plurality of wireless devices and a RAN node. The CN
node
comprises a processor and at least one memory that stores processor-executable
instructions, wherein the processor interfaces with the at least one memory to
execute
the processor-executable instructions, whereby the CN node is operable to
perform a
receive operation, a store operation, and a transmit operation. In the receive
operation,
the CN node is operable to receive, from the RAN node or one of the wireless
devices,
a message including a downlink Radio Coverage Category (RCC) value and an
uplink
RCC value associated with the one wireless device. In the store operation, the
CN node
is operable to store the downlink RCC value and the uplink RCC value
associated with
the one wireless device. In the transmit operation, the CN node is operable to
transmit,
to the RAN node, a paging message for the one wireless device when a downlink
payload becomes available for the one wireless device, wherein the paging
message
includes the downlink RCC value and the uplink RCC value associated with the
one
wireless device. The CN node configured to operate in this manner will address
the
need in the state-of-the-art by effectively using scarce radio resources,
reducing
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interference to the network, and reducing the consumption of the wireless
device's
battery power, etcetera, during the initial phase of data transmission.
In yet another aspect, the present disclosure provides a method in a CN node
configured to communicate with a plurality of wireless devices and a RAN node.
The
method comprises a receive step, a store step, and a transmit step. In the
receive step, a
message is received from the RAN node or one of the wireless devices, wherein
the
message includes a downlink Radio Coverage Category (RCC) value and an uplink
RCC value associated with the one wireless device. In the store step, the
downlink
RCC value and the uplink RCC value associated with the one wireless device are
stored. In the transmit step, a paging message for the one wireless device is
transmitted
to the RAN node when a downlink payload becomes available for the one wireless
device, wherein the paging message includes the downlink RCC value and the
uplink
RCC value associated with the one wireless device. The method will address the
need
in the state-of-the-art by effectively using scarce radio resources, reducing
interference
to the network, and reducing the consumption of the wireless device's battery
power,
etcetera, during the initial phase of data transmission.
Additional aspects of the invention will be set forth, in part, in the
detailed
description, figures and any claims which follow, and in part will be derived
from the
detailed description, or can be learned by practice of the invention. It is to
be
understood that both the foregoing general description and the following
detailed
description are exemplary and explanatory only and are not restrictive of the
invention
as disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the present invention may be obtained by
reference to
the following detailed description when taken in conjunction with the
accompanying
drawings:
FIGURE 1 is a diagram of an exemplary wireless communication network in
accordance with an embodiment of the present disclosure;
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FIGURE 2 is a signal flow diagram illustrating a downlink RCC value
determination process that occurs during a wireless device originated transfer
in
accordance with an embodiment of the present disclosure;
FIGURE 3 is a diagram illustrating different wireless devices with different
downlink RCC values being addressed by the same resource assignment message in
accordance with an embodiment of the present disclosure;
FIGURE 4 is a signal flow diagram illustrating an uplink RCC value
determination process that occurs during a wireless device originated transfer
in
accordance with an embodiment of the present disclosure;
FIGURE 5 is a signal flow diagram illustrating a process associated with a
wireless device terminated transfer in accordance with an embodiment of the
present
disclosure;
FIGURE 6 is a flowchart of a method implemented in a wireless device in
accordance with an embodiment of the present disclosure;
FIGURE 7 is a block diagram illustrating structures of an exemplary wireless
device in accordance with an embodiment of the present disclosure;
FIGURES 8A-8B is a flowchart of a method implemented in a RAN node in
accordance with an embodiment of the present disclosure;
FIGURE 9 is a block diagram illustrating structures of an exemplary RAN node
in accordance with an embodiment of the present disclosure;
FIGURE 10 is a flowchart of a method implemented in a CN node in
accordance with an embodiment of the present disclosure;
FIGURE 11 is a block diagram illustrating structures of an exemplary CN node
in accordance with an embodiment of the present disclosure;
FIGURE 12 is a signal flow diagram illustrating additional steps in the uplink
RCC value determination process that occur during the wireless device
originated
transfer as shown in FIGURE 4 in accordance with another embodiment of the
present disclosure;
FIGURE 13 is a flowchart illustrating additional steps in the method
implemented in the wireless device shown in FIGURE 6 in accordance with
another
embodiment of the present disclosure; and
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FIGURE 14 is a flowchart illustrating an additional step in the method
implemented in the CN node shown in FIGURE 10 in accordance with another
embodiment of the present disclosure.
5 DETAILED DESCRIPTION
To describe the technical features of the present disclosure, a discussion is
provided first to describe an exemplary wireless communication network which
includes multiple wireless devices, multiple RAN nodes, and a CN node each of
which
are configured in accordance with the present disclosure (see FIGURE 1). Then,
a
10 discussion is provided to explain the basic techniques and use cases
implemented by
the wireless device, the RAN node and the CN node in accordance with the
present
disclosure (see FIGURES 2-5). Thereafter, a discussion is provided to explain
in more
detail the various techniques implemented by each of the wireless device, the
RAN
node and the CN node in accordance with the present disclosure (see FIGURES 6-
11).
Finally, a discussion is provided to explain how the network can be updated
with
coverage class information by the wireless device in accordance with another
embodiment of the present disclosure (see FIGURES 12-14).
Exemplary Wireless Communication Network 100
Referring to FIGURE 1, there is illustrated an exemplary wireless
communication network 100 in accordance with the present disclosure. The
wireless
communication network 100 includes multiple RAN nodes 1021 and 1022 (only two
shown) and a core network 106 (e.g., CN node 107) which interface with
multiple
wireless devices 1041, 1042, 1043... 104õ. The wireless communication network
100
also includes many well-known components, but for clarity, only the components
needed to describe the features of the present disclosure are described
herein. Further,
the wireless communication network 100 is described herein as being a
GSM/EGPRS
wireless communication network 100 which is also known as an EDGE wireless
communication network 100. However, those skilled in the art will readily
appreciate
that the techniques of the present disclosure which are applied to the
GSM/EGPRS
wireless communication network 100 are generally applicable to other types of
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wireless communication systems, including, for example, WCDMA, LTE, and
WiMAX systems.
The wireless communication network 100 includes the RAN nodes 1021 and
1022 (only two shown) which provide network access to the wireless devices
1041,
1042, 1043... 104õ. In this example, the RAN node 1021 is providing network
access
to wireless device 1041 while the RAN node 1022 is providing network access to
wireless devices 1042, 1043...104õ. The RAN nodes 1021 and 1022 are connected
to the
core network 106 (e.g., EGPRS core network 106) and, in particular, to the CN
node
107. The core network 106 is connected to an external packet data network
(PDN)
108, such as the Internet, and a server 110 (only one shown). The wireless
devices
1041, 1042, 1043...104õ may communicate with one or more servers 110 (only one
shown) connected to the core network 106 and/or the PDN 108.
The wireless devices 1041, 1042, 1043...104õ may refer generally to an end
terminal (user) that attaches to the wireless communication network 100, and
may
refer to either a MTC device or a non-MTC device. Further, the term "wireless
device" is generally intended to be synonymous with the term "User Equipment,"
or
UE, as that term is used by the 3rd-Generation Partnership Project (3GPP), and
includes standalone wireless devices, such as terminals, cell phones, smart
phones,
tablets, and wireless-equipped personal digital assistants, as well as
wireless cards or
modules that are designed for attachment to or insertion into another
electronic
device, such as a personal computer, electrical meter, etc.
Likewise, the RAN nodes 1021 and 1022 may refer in generally to a base
station in the wireless communication network 100, and may refer to RAN nodes
1021
and 1022 that are controlled by a physically distinct radio network controller
as well
as to more autonomous access points, such as the so-called evolved Node Bs
(eNodeBs) in Long-Term Evolution (LTE) networks.
Each wireless device 1041, 1042, 1043...104õ may include a transceiver circuit
1101, 1102, 1103... 110õ for communicating with the RAN nodes 1021 and 1022,
and a
processing circuit 1121, 1122, 1123...112õ for processing signals transmitted
from and
received by the transceiver circuit 1101, 1102, 1103...110õ and for
controlling the
operation of the corresponding wireless device 1041, 1042, 1043...104,,.
The
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transceiver circuit 1101, 1102, 1103 ...110õ may include a transmitter 1141,
1142,
1143... 114õ and a receiver 1161, 1162, 1163...116,, which may operate
according to
any standard, e.g., the GSM/EDGE standard. The processing circuit 1121, 1122,
1123... 112õ may include a processor 1181, 1182, 1183...11811 and a memory
1201, 1202,
1203...120õ for storing program code for controlling the operation of the
corresponding wireless device 1041, 1042, 1043...104õ. The program code may
include code for performing the procedures as described hereinafter with
respect to
FIGURES 6 and 13.
Each RAN node 1021 and 1022 may include a transceiver circuit 1221 and 1222
for communicating with wireless devices 1041, 1042, 1043...104,, a processing
circuit
1241 and 1242 for processing signals transmitted from and received by the
transceiver
circuit 1221 and 1222 and for controlling the operation of the corresponding
wireless
access node 1021 and 1022, and a network interface 1261 and 1262 for
communicating
with the core network 106. The transceiver circuit 1221 and 1222 may include a
transmitter 1281 and 1282 and a receiver 1301 and 1302, which may operate
according
to any standard, e.g., the GSM/EDGE standard. The processing circuit 1241 and
1242
may include a processor 1321 and 1322 and a memory 1341 and 1342 for storing
program code for controlling the operation of the corresponding wireless
access node
1021 and 1022. The program code may include code for performing the procedures
as
described hereinafter with respect to FIGURES 8A-8B.
The CN node 107 (e.g., SGSN 107, MME 107) may include a transceiver
circuit 136 for communicating with the RAN nodes 1021 and 1022, a processing
circuit 138 for processing signals transmitted from and received by the
transceiver
circuit 136 and for controlling the operation of the RAN nodes 1021 and 1022,
and a
network interface 140 for communicating with the RAN nodes 1021 and 1022. The
transceiver circuit 136 may include a transmitter 142 and a receiver 144,
which may
operate according to any standard, e.g., the GSM/EDGE standard. The processing
circuit 138 may include a processor 146 and a memory 148 for storing program
code
for controlling the operation of the CN node 107. The program code may include
code for performing the procedures as described hereinafter with respect to
FIGURES
10 and 14.
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Basic Techniques and Exemplary Use Cases of the Present Disclosure
The present disclosure provides a new mechanism for enhancing the radio
coverage based on the exchange of uplink and downlink radio condition
information,
referred to as Radio Coverage Category (RCC) values, between the wireless
device
1042 (for example) and the network 100 (e.g., the RAN node 1022 and/or the CN
node
107) for use in data transmission (e.g., control plane related signaling or
user plane
related payload transmission). It is to be noted that the other wireless
devices 1041,
1043...104õ and RAN node 1021 can also implement the new mechanism of the
present disclosure. The disclosed techniques are based on an exchange of
estimated
RCC values between the network 100 and the wireless device 1042 that are used
to
apply a number (e.g., a pre-defined number) of repeated transmissions on the
radio
interface. The RCC values may be estimated for the downlink (e.g., from the
wireless
device 1042 perspective) and for the uplink (e.g., from the network 100
perspective).
The RCC values may be stored in the relevant network nodes such as the RAN
node
1022 and the CN node 107 and in the wireless device 1042 for use in
determining the
appropriate number of repeated transmissions for subsequent data
transmissions, for
example, at paging occasions.
The disclosed techniques can implement one or more of the following
principles:
= The uplink and downlink radio conditions between the RAN node 1022
and a given wireless device 1042 may be categorized, organized, or divided
into a
range of RCC values.
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= A given RCC value is mapped into a number of repeated transmissions.
The mapping of each RCC value to a specific number of repeated transmissions
may
be standardized and known to the network 100 (e.g., the RAN node 1022 and/or
the
CN node 107) and the wireless device 1042. Hence, a given RCC value may
implicitly or explicitly indicate the number of repeated transmissions and may
therefore be known to the involved entities 1022, 107, and 1042 in a
deterministic
manner. Alternatively, the mapping may be adjustable and signaled (e.g., in
the
system information) to the involved entities 1022, 107, and 1042.
= The wireless device 1042 provides an estimate of its downlink RCC
value (with relation to its serving RAN node 1022/cell) to the network 100 in
the
applicable procedures and/or messages.
= The RAN node 1022 provides an estimate of its uplink RCC value in
relation to a specific wireless device 1042 to that wireless device 1042 in
the
applicable procedures and/or messages.
= The network 100 may
store the information about the uplink and
downlink RCC values in the nodes such as the RAN node 1022 and the CN node 107
that would re-use this information in subsequent radio transmissions.
= The wireless device 1042 may store the information about the uplink and
downlink RCC values and re-use this information in subsequent radio
transmissions.
= The RAN node 1022
may upload wireless device specific RCC values for
the uplink and downlink associated with a particular wireless device 1042 to
the
relevant CN node 107 (e.g., SGSN 107, MME 107). Alternatively, wireless device
specific RCC information may be conveyed by the wireless device 1042 to the CN
node 107, for example, during Non-Access Stratum (NAS) signaling.
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= The RAN node 1022 applies a number of downlink repeated
transmissions over the radio interface based on the available wireless device
specific
downlink RCC value. The RCC value used for determining the number of repeated
transmissions on the downlink may be based on the last received RCC value from
the
5 wireless device 1042, network 100 (e.g. RAN node 1022) estimates of the
downlink
RCC value (e.g., based on uplink radio quality), or a running average of the
received
downlink RCC values and/or the network 100 (e.g. RAN node 1022) estimated
downlink RCC values.
= The wireless device 1042 applies a number of uplink repeated
10 transmissions based on the available uplink RCC value received from the
RAN node
1022. The RCC value used for determining the number of repeated transmissions
on
the uplink may be based on the latest estimated uplink RCC value received from
the
network 100 (e.g., the RAN node 1022), the wireless device 1042 estimates of
the
uplink RCC value (e.g., based on downlink radio quality), or a running average
of
15 received uplink RCC values and/or the wireless device 1042 estimated
uplink RCC
values.
= For the case when the wireless device 1042 makes its first contact with
the RAN node 1022 after the wireless device's initial deployment and power on
in the
field or when the wireless device 1042 wakes up to perform a system access
procedure following a period of sleep, the number of repeated retransmissions
the
wireless device 1042 uses when performing a random access procedure (e.g.,
sending
a first message on the Random Access Channel (RACH), such as a Channel Request
message on the RACH) may be based on (1) the wireless device's own independent
assessment of an appropriate uplink RCC value, or (2) the wireless device's
preconfigured information of an appropriate uplink RCC value.
= The network 100 (e.g., the RAN node 1022) applies a number of repetitions
based on a stored RCC of the wireless device 1042. This can, for example,
apply
when paging the wireless device 1042 or responding to a first message on the
Random
Access Channel (RACH), such as a Channel Request message on the RACH.
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= The RAN node 1022 and the wireless device 1042 can make use of the
knowledge about the wireless device's type of usage, for example, being a
stationary
device, that can be preconfigured in the wireless device 1042 and in e.g.,
subscription
data in the network 100 when deciding whether or not to apply a number of
repetitions according to the stored RCC.
Referring to FIGURE 2, there is a signal flow diagram illustrating a downlink
RCC value determination process that occurs during a wireless device
originated
transfer in accordance with an embodiment of the present disclosure. Prior to
accessing the RAN node 1022, the wireless device 1042 receives (e.g.,
monitors) some
Radio Access Technology (RAT) specific set of control channels in order to,
for
example, obtain the synchronization with the RAN node 1022 (see FIGURE 2's
step
1). In the case of Global System for Mobile (GSM), prior to accessing the
GSM/EDGE Radio Access Network (GERAN), the wireless device 1042 will monitor
the Synchronization Channel (SCH) and Frequency Correction Channel (FCCH).
After the decoding of the SCH, the wireless device 1042 may also decode the
System
Information (SI) transmitted on the Broadcast Control Channel (BCCH). The SCH,
FCCH, and BCCH in GSM are constantly transmitting on full power.
The wireless device 1042 utilizes the received control channels to estimate
its
experienced downlink radio condition based on, for example, a Received Signal
Strength Indicator (RSSI), a received estimated quality (e.g., the decoded
quality of
the SCH and System Information), or any other metric that estimates the
wireless
device's downlink radio condition (see FIGURE 2's step 2).
International Application Number: IB2015054746
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Mel' With I LJel I Id! IU 101 LL fry!
Lt.) 10
REPLACEMENT SHEET
17
The wireless device 1042 maps the estimated downlink radio condition to one
of multiple downlink RCC values (see FIGURE 2's step 3 and graph "A"). In this
example, an RSSI-based mapping is illustrated where the estimated RSSI value
is
mapped to one of four different downlink RCC values. It is to be noted that
the
number of downlink RCC values and the number of transmissions for each of the
downlink RCC values illustrated in FIGURE 2 (i.e., 1 transmission for RCC 0, 2
transmissions for RCC 1, 4 transmissions for RCC 2, and 16 transmissions for
RCC
3) are provided as examples. In other cases, there may be fewer or more
downlink
RCC values and/or different numbers of transmissions may be associated with
the
downlink RCC values.
The wireless device 1042 transmits a message 202 which includes the
downlink RCC value to the RAN node 1022 (see FIGURE 2's step 4). More
specifically, when accessing the RAN node 1022 for some wireless device
originated
data transmission, the wireless device 1042 provides the downlink specific RCC
value
in an appropriate RRC message 202 (e.g., the Channel Request message 202 in
GERAN, the RRCConnectionRequest 202 in LTE or UMTS) or some message during
a radio capability acquisition procedure. A means by which the wireless device
1042
can communicate a downlink specific RCC value to the RAN node 1022 (e.g., BSS
1022) is described in U.S. Patent Application No. 61/968,621, filed on March
21,
2014, entitled "Accelerated System Access Procedure (ASAP)".
The RAN node 1022 determines a downlink RCC value to be used for the
wireless device 1042 (see FIGURE 2's step 5). The RAN node 1022 can determine
the downlink RCC value to be used for the wireless device 1042 based on: (1)
the
received first downlink RCC value (e.g., the downlink RCC value of FIGURE 2's
step 4); (2) an estimated downlink RCC value (e.g., based on uplink radio
conditions); or (3) a running average of previously received first downlink
RCC
values and/or previously estimated downlink RCC values. For instance, the RAN
node 1022 may estimate the downlink specific RCC value based on the uplink
radio
condition for the wireless device 1042 and may combine this with the RCC value
estimated by the wireless device 1042 itself when determining the downlink RCC
AMENDED SHEET
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value to be used for the wireless device 1042. Further, the particular
algorithm used
by the RAN node 1022 for determining the used downlink RCC value may be
implementation dependent.
The RAN node 1022 maps the determined downlink RCC value to a number of
repeated downlink transmissions to be used for downlink message(s) 205 to the
wireless device 1042 (see FIGURE 2's step 6 and graph "A"; note: the RAN node
1022
also maps the downlink RCC value received in FIGURE 2's step 4 to a number of
repeated downlink transmissions to be used for the downlink message 204
transmitted
to the wireless device 1042). Then, the RAN node 1022 transmits to the
wireless device
1042 a message 204 (e.g., Immediate Assignment message) that is repeated
according
to the downlink RCC value received from the wireless device 1042 (see FIGURE
2's
step 6a). The message 204 would include the RAN node's determined downlink RCC
value from FIG. 2's step 5 if it is different than the wireless device's
downlink RCC
value in message 202. Thereafter, the RAN node 1022 transmits to the wireless
device
1042 the subsequent downlink message(s) 205 having a number of repeated
downlink
transmissions based on the RAN node's determined downlink RCC value (see
FIGURE
2's step 7). Basically, if the RAN node 1022 decides to use a downlink RCC
value
that is different than the downlink RCC value sent by the wireless device 1042
in
FIGURE 2's step 4, then the RAN node 1022 will indicate this to the wireless
device
1042 by including the determined downlink RCC value in the first downlink
message
204 which is always sent with repeated transmissions according to the downlink
RCC
value sent by the wireless device 1042 in FIGURE 2's step 4.
It should be noted that the number of repetitions can be different, for
example,
depending on the logical channel that is associated with the downlink message
204 or
205 to be transmitted to the wireless device 1042. For example, in GERAN, the
RAN
node 1022 can apply a first number of repeated transmissions according to the
determined downlink RCC value when transmitting the Immediate Assignment
message 204 on the Access Grant Channel (AGCH), but apply a second number of
repetitions, for example, when transmitting a Packet Power Control/Timing
Advance
message 205 on the Packet Associated Control Channel (PACCH). Similarly, in
the
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RAN node 1022, the number of repetitions used for Signaling Radio Bearers
might be
different from the number used for Data Radio Bearers.
It should be noted that when a repetition-only based scheme is used, and when
multiple wireless devices 1042, 1043 and 1044 (for example) are addressed by
the
same message 204 or 205, there is no need for all the wireless devices 1042,
1043 and
1044 to have the same downlink RCC value. The number of repetitions used may
instead be determined by the wireless device 1044 (for example) which has the
highest downlink RCC value (i.e., the worst coverage). An example of this
message
format is illustrated in FIGURE 3, where wireless devices 1042, 1043 and 1044
are
addressed by the same resource assignment message 204. In this example, the
resource assignment message 204 on the same AGCH is repeated 16 times due to
the
coverage class of wireless device 1044 (mapped to 16 repetitions), while
wireless
devices 1042 and 1043 which have lower coverage classes (i.e., fewer
repetitions
needed) will be able to read the same resource assignment message 204 after
decoding the respective number of repetitions according to their RCC coverage
class
(i.e., 4 repetitions for wireless device 1042 and 8 repetitions for wireless
device 1043).
In some embodiments, the same number of repeated transmissions according
to the wireless device's downlink RCC value (which can be different depending
on
the logical channel considered) may be applied to any subsequent downlink
messages
204, control or user plane messages 204, until the RAN node 1022 determines
e.g.,
through the assistance of ACK/NACK or Measurement Report information supplied
by the wireless device 1042 that a different downlink RCC value should be used
for
the wireless device 1042 (see FIGURE 2's step 8). Any change in the downlink
RCC
value (number of repeated transmissions) may be signaled by the RAN node 1022
in
the control plane either explicitly by means of dedicated signaling or
implicitly e.g.,
through in-band signaling to the wireless device 1042 (see FIGURE 2's step 9).
When explicitly signaling a change in the downlink RCC value, the number of
repeated transmissions used by the RAN node 1022 is determined using the
downlink
RCC value it has stored for the wireless device 1042 prior to deciding to make
the
change to the downlink RCC value. Similar to the downlink, the RAN node 1022
can
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estimate the RCC value applicable in the uplink for a given wireless device
1042. This
process is described next with respect to FIGURE 4.
Referring to FIGURE 4, there is a signal flow diagram illustrating an uplink
RCC value determination process that occurs during a wireless device
originated
5 transfer in accordance with an embodiment of the present disclosure. The
RAN node
1022 receives the message 202 (e.g., Channel Request message 202, RRC
Connection
Request message 202) on the RACH from the wireless device 1042 (see FIGURE 4's
step 1). For the case when the wireless device 1042 makes its first contact
with the
RAN node 1022 after the wireless device's initial deployment and power on in
the
10 field or when it wakes up to perform a system access procedure following
a period of
sleep, the number of repeated retransmissions the wireless device 1042 uses
when
sending RACH bursts for the Channel Request message 202 (RRC Connection
Request message 202) on the RACH may be based, for example, on the wireless
device's own independent assessment of an appropriate uplink RCC value (e.g.,
based
15 on the estimated downlink radio condition of FIGURE 2's step 2) or pre-
configured
information (see FIGURE 4's note 1).
The RAN node 1022 estimates an uplink RCC value based on a quality (e.g.,
RSSI) of the received message 202 (see FIGURE 4's step 2 and graph "A"). In
this
example, an RSSI-based mapping measurement is illustrated where an estimated
20 RSSI value of uplink radio conditions associated with the received
message 202 is
mapped to one of four different uplink RCC values. It is to be noted that the
number
of uplink RCC values and the number of transmissions for uplink RCC values
illustrated in FIGURE 4 (i.e., 1 transmission for RCC 0, 2 transmissions for
RCC 1, 4
transmissions for RCC 2, and 16 transmissions for RCC 3) are provided as
examples.
In other cases, there may be fewer or more uplink RCC values and/or different
numbers of transmissions may be associated with the uplink RCC values.
The RAN node 1022 adds (inserts, includes) the uplink RCC value to the
message 204 (e.g., Immediate Assignment message 204 or any other RRC message
204
following the Channel Request message 202) transmitted to the one wireless
device
1042 (see FIGURE 4's step 3). The uplink RCC value communicated to the
wireless
device 1042 may be, for example, the last uplink RCC value estimated by the
RAN
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node 1022, a running average of the previously estimated uplink RCC values,
and/or
estimated or used downlink RCC values for that particular wireless device
1042.
The wireless device 1042 maps the uplink RCC value into a number of uplink
repetitions (see FIGURE 4's step 4 and graph "A'). Then, prior to the
termination of
the connection, the wireless device 1042 applies the number of uplink
repetitions on
all subsequent uplink messages 206 transmitted on the RACH and on the uplink
of
any subsequently assigned Packet Data Traffic Channels (PDTCHs) or Packet
Associated Control Channels (PACCHs) to the RAN node 1022 (see FIGURE 4's step
5).
Following the termination of the connection the wireless device 1042 could
optionally continue to use its stored uplink RCC value (see FIGURE 4's step 9)
for
subsequent uplink messages 202 transmitted on the RACH (see FIGURE 4's step 1)
if
they are transmitted within a limited time period following its most recent
reception
of the uplink RCC value in the message 204 (see FIGURE 4's step 3).
The wireless device 1042 continues to use the uplink RCC value for the uplink
messages 206 until a new uplink RCC value is received from the RAN node 1022
(see
FIGURE 4's step 6). The wireless device 1042 can receive the new uplink RCC
value
from the RAN node 1022, for example, either in a control message or in an
implicit
manner (e.g., Packet Uplink ACK/NACK message indicating a failed uplink
reception).
The RAN node 1022 may store the RCC values applicable to both the uplink
and downlink along with a Temporary Logical Link Identifier (TLLI) or other
local
relevant identifier of the wireless device 1042 (see FIGURE 4's step 7; note:
step 7 is
also typically performed immediately after or as part of step 2). Then, upon
termination of the connection (e.g., RRC connection) between the RAN node 1022
and
the wireless device 1042, the RAN node 1022 may transmit the RCC values
applicable
to both the uplink and downlink along with a TLLI or other local relevant
identifier
of the wireless device 1042 to the CN node 107 (see FIGURE 4's step 8). For
instance, the RAN node 1022 can include the uplink and downlink RCC values as
supplemental information when sending the received messages 206 of step 5 to
the
CN 107. Additionally or alternatively, the wireless device 1042 may store the
RCC
values applicable to both the uplink and downlink (see FIGURE 4's step 9;
note: step
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9 can also occur immediately after step 1 and step 4). Furthermore, the
wireless
device 1042 may transmit the RCC values for both the uplink and downlink to
the CN
node 107, for example, via NAS signaling (e.g., within a periodic Routing Area
Update (RAU) message) (see FIGURE 4's step 10). In this case, if wireless
device
1042 performs step 10 then the RAN node 1022 would not need to include the
uplink
and downlink RCC values as supplemental information when sending the received
messages 206 of step 5 to the CN 107.
Referring to FIGURE 5, there is a signal flow diagram illustrating a process
associated with a wireless device terminated transfer in accordance with an
embodiment of the present disclosure. The CN node 107 supplies the RAN node
1022 with stored RCC values for the uplink and the downlink for the wireless
device
1042 during a subsequent wireless device terminated transfer. More
specifically, the
CN node 107 transmits a paging message 208 with the stored RCC values for
uplink
and downlink when a downlink payload becomes available for the wireless device
1042 (see FIGURE 5's step 1). Recall: the RAN node 1022 and/or the wireless
device
1042 at the end of the previous connection uploaded the RCC values for the
uplink
and downlink to the CN node 107 (see FIGURE 4's steps 8 and 10).
The RCC values for both uplink and downlink may be sent together in the
paging message 208 with a time stamp indicating the time that the RCC values
had
been uploaded to the CN node 107 and including cell identifier information
about the
cell where the wireless device 1042 was connected when these RCC values were
obtained. This information and if desired additional information may also be
provided in the paging message 208 to enable the RAN node 1022 to assess the
reliability of the downlink and uplink RCC values. The RCC values for uplink
and
downlink may be sent with the paging message 208 using the relevant interface,
e.g.,
Gb, Iu, SlAP.
The RAN node 1022 (e.g., the BSC 1022 in 2G, the RNC 1022 in 3G, or the
eNB 1022 in LTE) may use the received downlink RCC value to determine the
paging
repetition number for the paging message 208' which is to be transmitted to
the
wireless device 1042 (see FIGURE 5's step 2). The RAN node 1022 then transmits
the paging message 208' using the determined paging repetition number to the
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wireless device 1042 (see FIGURE 5's step 3). Furthermore, the RAN node 1022
may
add the uplink RCC value to the paging message 208' itself and thus enable the
wireless device 1042 to map and use a specific number of uplink repetitions
during
the random access procedure triggered to transmit a corresponding page
response 210
to the RAN node 1022 (see FIGURE 5's steps 4 and 5). Alternatively, the RAN
node
1022 can determine that the RCC values for the uplink and downlink received
from
the CN node 107 are outdated, then in this case the paging message 208' sent
to the
wireless device 1042 may be repeated a maximum number of times, and the uplink
RCC value communicated in the paging message 208' to the wireless device 1042
may be set to the highest value (i.e., a maximum number of repetitions) (see
FIGURE
5's note 1). The subsequent behavior by the wireless device 1042 and the RAN
node
1022 may be the same as described above in reference to wireless device
originated
transfer in FIGURES 2-4.
Detailed Techniques Implemented by Devices
Referring to FIGURE 6, there is a flowchart of a method 600 implemented in a
wireless device 1042 (for example) in accordance with an embodiment of the
present
disclosure. At step 602, the wireless device 1042 receives (e.g., monitors)
some RAT
specific set of control channels in order to, for example, obtain the
synchronization
with the RAN node 1022 (see FIGURE 2's step 1). At step 604, the wireless
device
1042 estimates a downlink radio condition based on a signal quality (e.g.,
RSSI) of the
received control channels (see FIGURE 2's step 2). At step 606, the wireless
device
1042 maps the estimated downlink radio condition to one of multiple downlink
RCC
values (see FIGURE 2's step 3 and graph "A"). At step 608, the wireless device
1042
transmits a message 202 (e.g. Channel Request message 202) which includes the
downlink RCC value to the RAN node 1022 (see FIGURE 2's step 4). If the
message
202 (e.g., Channel Request message 202) is the wireless device's first contact
with
the RAN node 1022, then the wireless device 1042 may have previously
determined at
step 608' an estimated number of repeated uplink transmissions (e.g., based on
the
estimated downlink radio condition or preconfigured information) to use when
transmitting the message 202 to the RAN node 1022 (see FIGURE 4's note 1).
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At step 610, the wireless device 1042 receives a downlink message 204 (e.g.,
Immediate Assignment message 204) having a number of repeated downlink
transmissions and including an uplink RCC value (see FIGURE 2's step 7 and
FIGURE 4's step 3). Recall: the number of repeated downlink transmissions in
the
downlink message 204 is based on the downlink RCC value sent by the wireless
device 1042 in message 202 (see FIGURE 2's step 4 and FIGURE 4's step 1).
Plus,
the message 204 may include the RAN node's determined downlink RCC value
which is to be used for the subsequent downlink messages 205 (see FIGURE 2's
step
6a). At step 612, the wireless device 1042 maps the uplink RCC value (included
in
message 204) to determine a number of uplink repetitions (see FIGURE 4's step
4
and graph "A'). At step 614, the wireless device 1042 transmits an uplink
message
206 that is repeated according to the number of repeated uplink transmissions
to the
RAN node 1022 (see FIGURE 4's step 5). The wireless device 1042 would continue
to use the uplink RCC value for the subsequent uplink messages 206 until a new
uplink RCC value is received from the RAN node 1022 (see FIGURE 4's step 6).
At
step 616, the wireless device 1042 stores the RCC values applicable to both
the uplink
and downlink (see FIGURE 4's step 9). At step 618, the wireless device 1042
may
transmit the RCC values for both the uplink and downlink to the CN node 107
(see
FIGURE 4's step 10).
At step 620, the wireless device 1042 receives from the RAN node 1022 the
paging message 208' having a number of downlink repetitions and an uplink RCC
value (see FIGURE 5's step 3; recall: the paging message 208' would be sent
when
the CN node 107 has new downlink payload for the wireless device 1042). The
number of repeated downlink repetitions used in the paging message 208' may be
based on the downlink RCC value previously sent by the wireless device 1042 or
the
RAN node 1022 to the CN node 107 (see FIGURE 5's steps 1-2) or a maximum
number of downlink repetitions (see FIGURE 5's note 1). The uplink RCC value
in
the paging message 208' may be the uplink RCC value previously sent by the
wireless device 1042 or the RAN node 1022 to the CN node 107 (see FIGURE 5's
steps 1-2) or a maximum number of uplink repetitions (see FIGURE 5's note 1).
At
step 622, the wireless device 1042 maps the uplink RCC value to determine a
specific
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number of uplink repetitions to use when transmitting the corresponding page
response 210 to the RAN node 1022 (see FIGURE 5's step 4). At step 624, the
wireless device 1042 transmits the page response 210 using the determined
number of
uplink repetitions to the RAN node 1022 (see FIGURE 5's step 5). For a more
5 detailed
discussion about steps 602, 604, 606, 608, 610, 612, 614, 616, 618, 620, 622
and 624 reference is made to FIGURES 2, 4 and 5.
Referring to FIGURE 7, there is a block diagram illustrating structures of an
exemplary wireless device 1042 configured to interact with the RAN node 1022
and
the CN node 107 in accordance with an embodiment of the present disclosure. In
an
10 embodiment,
the wireless device 1042 may comprise a first receive module 702, an
estimate module 704, a first map module 706, a first transmit module 708, a
second
receive module 710, a second map module 712, a second transmit module 714, a
store
module 716, a third transmit module 718, a third receive module 720, a third
map
module 722, and a fourth transmit module 724.
15 The first
receive module 702 is configured to receive (e.g., monitor) some
RAT specific set of control channels in order to, for example, obtain the
synchronization with the RAN node 1022 radio interface (see FIGURE 2's step
1).
The estimate module 704 is configured to estimate a downlink radio condition
based
on a signal quality (e.g., RSSI) of the received control channels (see FIGURE
2's step
20 2). The
first map module 706 is configured to map the estimated downlink radio
condition to one of multiple downlink RCC values (see FIGURE 2's step 3 and
graph
"A"). The first transmit module 708 is configured to transmit a message 202
(e.g.
Channel Request message 202) which includes the downlink RCC value to the RAN
node 1022 (see FIGURE 2's step 4). The first transmit module 708 may include a
25 determine
module 708' configured to determine an estimated number of repeated
uplink transmissions (e.g., based on the estimated downlink radio condition or
preconfigured information) to use when transmitting the message 202 to the RAN
node
1022 if the message 202 (e.g., Channel Request message 202) is the wireless
device's
first contact with the RAN node 1022, (see FIGURE 4's note 1).
The second receive module 710 is configured to receive a downlink message
204 (e.g., Immediate Assignment message 204) having a number of repeated
downlink
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transmissions and including an uplink RCC value (see FIGURE 2's step 7 and
FIGURE 4's step 3). Recall: the number of repeated downlink transmissions in
the
downlink message 204 is based on the downlink RCC value sent by the wireless
device 1042 in message 202 (see FIGURE 2's step 4 and FIGURE 4's step 1).
Plus,
the message 204 may include the RAN node's determined downlink RCC value
which is to be used for the subsequent downlink messages 205 (see FIGURE 2's
step
6a). The second map module 712 is configured to map the uplink RCC value
(included in message 204) to determine a number of uplink repetitions (see
FIGURE
4's step 4 and graph "A'). The second transmit module 714 is configured to
transmit
an uplink message 206 that has the estimated number of repeated uplink
transmissions
to the RAN node 1022 (see FIGURE 4's step 5). The second transmit module 714
would continue to use the uplink RCC value for the subsequent uplink messages
206
until a new uplink RCC value is received from the RAN node 1022 (see FIGURE
4's
step 6). The store module 716 is configured to store the RCC values applicable
to
both the uplink and downlink (see FIGURE 4's step 9). The third transmit
module
718 is configured to transmit the RCC values for both the uplink and downlink
to the
CN node 107 (see FIGURE 4's step 10).
The third receive module 720 is configured to receive from the RAN node
1022 the paging message 208' having a number of downlink repetitions and an
uplink
RCC value (see FIGURE 5's step 3; recall: the paging message 208' would be
sent
when the CN node 107 has new downlink payload for the wireless device 1042).
The
number of repeated downlink repetitions used in the paging message 208' may be
based on the downlink RCC value previously sent by the wireless device 1042 or
the
RAN node 1022 to the CN node 107 (see FIGURE 5's steps 1-2) or a maximum
number of downlink repetitions (see FIGURE 5's note 1). The uplink RCC value
in
the paging message 208' may be the uplink RCC value previously sent by the
wireless device 1042 or the RAN node 1022 to the CN node 107 (see FIGURE 5's
steps 1-2) or a maximum number of uplink repetitions (see FIGURE 5's note 1).
The
third map module 722 is configured to map the uplink RCC value to determine a
specific number of uplink repetitions to use when transmitting the
corresponding
page response 210 to the RAN node 1022 (see FIGURE 5's step 4). The fourth
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transmit module 724 is configured to transmit the page response 210 using the
determined number of uplink repetitions to the RAN node 1022 (see FIGURE 5's
step
5).
As those skilled in the art will appreciate, the above-described modules 702,
704, 706, 708, 710, 712, 714, 716, 718, 720, 722 and 724 of the wireless
device 1042
may be implemented separately as suitable dedicated circuits. Further, the
modules
702, 704, 706, 708, 710, 712, 714, 716, 718, 720, 722 and 724 can also be
implemented using any number of dedicated circuits through functional
combination or
separation. In some embodiments, the modules 702, 704, 706, 708, 710, 712,
714, 716,
718, 720, 722 and 724 may be even combined in a single application specific
integrated circuit (ASIC). As an alternative software-based implementation,
the
wireless device 1042 may comprise a memory 1202, a processor 1182 (including
but not
limited to a microprocessor, a microcontroller or a Digital Signal Processor
(DSP),
etc.) and a transceiver 1102. The memory 1202 stores machine-readable program
code
executable by the processor 1182 to cause the wireless device 1042 to perform
the steps
of the above-described method 600.
Referring to FIGURES 8A-8B, there is a flowchart of a method 800
implemented in a RAN node 1022 (for example) in accordance with an embodiment
of
the present disclosure. At step 802, the RAN node 1022 transmits control
channels
(e.g., BCCH, SCH, FCCH) to enable the wireless device 1042 (for example) to
obtain
synchronization with the RAN node 1022 (see FIGURE 2's step 1). At step 804,
the
RAN node 1022 receives from the wireless device 1042 a message 202 (e.g.,
Channel
Request message 202) which includes the wireless device's downlink RCC value
(see
FIGURE 2's step 4). At step 806, the RAN node 1022 determines a downlink RCC
value to be used for the wireless device 1042 (see FIGURE 2's step 5). At step
808,
the RAN node 1022 maps the determined downlink RCC value to a number of
repeated downlink transmissions to be used for downlink message(s) 205
transmitted
to the wireless device 1042 (see FIGURE 2's step 6 and graph "A"; note: the
RAN
node 1022 also maps the downlink RCC value received in FIGURE 8's step 804 to
a
number of repeated downlink transmissions to be used for the downlink message
204
transmitted to the wireless device 1042). At step 809, the RAN node 1022
transmits a
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first downlink message 204 (e.g., Immediate Assignment message 204) to the
wireless
device 1042 (see FIGURE 2's step 7) where the number of repeated downlink
transmissions used for the downlink message 204 is based on the downlink RCC
value
sent by the wireless device 1042 in message 202 (see FIGURE 2's step 4). If
the
RAN node 1022 decides to use a downlink RCC value that is different than the
downlink RCC value received from the wireless device 1042 in step 804, then
the
RAN node 1022 will indicate this to the wireless device 1042 by including the
determined downlink RCC value from step 806 in the first downlink message 204.
Subsequent downlink messages 205 are then transmitted at step 810 by the RAN
node 1022 to the wireless device 1042 based on the determined downlink RCC
value
from step 806. At step 812, the RAN node 1022 determines e.g., through the
assistance of ACK/NACK or Measurement Report information supplied by the
wireless device 1042 that a new downlink RCC value should be used for the
wireless
device 1042 (see FIGURE 2's step 8). At step 814, the RAN node 1022 transmits
the
new downlink RCC value (number of repeated transmissions) to the wireless
device
1042 (see FIGURE 2's step 9). The number of repeated transmissions used by the
RAN node 1022 to transmit the message which contains the new downlink RCC
value is determined using the downlink RCC value it has stored for the
wireless
device 1042 prior to deciding to use a new downlink RCC value.
At step 816, the RAN node 1022 upon receiving the message 202 (e.g.,
Channel Request message 202) at step 804 will also estimate an uplink RCC
value
for the wireless device 1042 based on a quality (e.g., RSSI) of the received
message
202 (see FIGURE 4's step 2 and graph "A"). At step 818, the RAN node 1022 adds
(inserts, includes) the estimated uplink RCC value to the message 204 (e.g.,
Immediate
Assignment message 204) that is transmitted during step 810 to the one
wireless device
1042 (see FIGURE 4's step 3). At step 820, the RAN node 1022 receives from the
wireless device 1042 at least one uplink message 206 that has the number of
repeated
uplink transmissions which corresponds to the uplink RCC value sent in message
204
(see FIGURE 4's step 5). At step 822, the RAN node 1022 transmits a new uplink
RCC value if needed to the wireless device 1042 (see FIGURE 4's step 6). At
step
824, the RAN node 1022 stores the RCC values applicable to both the uplink and
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downlink along with a TLLI or other local relevant identifier of the wireless
device
1042 (see FIGURE 4's step 7). At step 826, the RAN node 1022 may transmit the
RCC values applicable to both the uplink and downlink to the CN node 107 along
with a TLLI or other local relevant identifier of the wireless device 1042
upon the
termination of the connection between the wireless device 1042 and the RAN
node
1022 (see FIGURE 4's step 8).
At step 828, the RAN node 1022 receives from the CN node 107 the paging
message 208 with the RCC values for uplink and downlink for the wireless
device
1042 when a downlink payload becomes available for the wireless device 1042
(see
FIGURE 5's step 1). At step 830a, the RAN node 1022 may use the received
downlink RCC value to determine the paging repetition number for the paging
message 208' which is to be transmitted to the wireless device 1042 (see
FIGURE 5's
step 2). At step 832a, the RAN node 1022 transmits the paging message 208'
(which
includes the uplink RCC value) using the determined paging repetition number
to the
wireless device 1042 (see FIGURE 5's step 3). At step 834a, the RAN node 1022
receives from the wireless device 1042 the page response 210 having a number
of
repeated uplink transmissions based on the uplink RCC value in the paging
message
208' (see FIGURE 5's step 5). Alternatively, after step 828 the RAN node 1022
at
step 830b determines that the RCC values for the uplink and downlink received
from
the CN node 107 are outdated, then in this case the paging message 208'
transmitted
at step 834b to the wireless device 1042 may be repeated a maximum number of
times and the uplink RCC value communicated in the paging message 208' to the
wireless device 1042 may be set to the highest RCC value (i.e., a maximum
number
of repetitions) (see FIGURE 5's note 1). It should be noted that in practice
the
wireless device 1042 would typically be listening according to the last
downlink RCC
value it conveyed to the network 100 and so it may not be very helpful for the
RAN
node 1022 to autonomously decide to use the maximum number of repetitions. At
step 834b, the RAN node 1022 receives from the wireless device 1042 the page
response 210 having a highest number of repeated uplink transmissions based on
the
highest uplink RCC value.
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Referring to FIGURE 9, there is a block diagram illustrating structures of an
exemplary RAN node 1022 configured to interact with a wireless device 1042 and
a
CN node 107 in accordance with an embodiment of the present disclosure. In an
embodiment, the RAN node 1022 may comprise a first transmit module 902, a
first
5 receive module 904, a first determine module 906, a map module 908, a
second
transmit module 909, a third transmit module 910, a second determine module
912, a
fourth transmit module 914, an estimate module 916, an add module 918, a
second
receive module 920, a fifth transmit module 922, a store module 924, a sixth
transmit
module 926, a third receive module 928, a use module 930a, a seventh transmit
module
10 932a, a fourth receive module 934a, a third determine module 930b, an
eighth transmit
module 932b, and a fifth receive module 934b.
The first transmit module 902 is configured to transmit control channels
(e.g.,
BCCH, SCH, FCCH) to enable the wireless device 1042 (for example) to obtain
synchronization with the RAN node 1022 (see FIGURE 2's step 1). The first
receive
15 module 904 is configured to receive from the wireless device 1042 a
message 202
(e.g., Channel Request message 202) which includes the wireless device's
downlink
RCC value (see FIGURE 2's step 4). The first determine module 906 is
configured
to determine a downlink RCC value to be used for the wireless device 1042 (see
FIGURE 2's step 5). The map module 908 is configured to map the determined
20 downlink RCC value to one of a multiple of downlink RCC values to
determine a
number of repeated downlink transmissions to be used for downlink message(s)
204
transmitted to the wireless device 1042 (see FIGURE 2's step 6 and graph "A" ;
note:
the map module 908 also maps the downlink RCC value received in FIGURE 2's
step
4 to a number of repeated downlink transmissions to be used for the downlink
message
25 204 transmitted to the wireless device 1042). The second transmit module
909 is
configured to transmit a first downlink message 204 (e.g., Immediate
Assignment
message 204) to the wireless device 1042 (see FIGURE 2's step 7) where the
number
of repeated downlink transmissions used for the downlink message 204 is based
on the
downlink RCC value sent by the wireless device 1042 in message 202 (see FIGURE
30 2's step 4) (see FIGURE 2's step 6a). If the first determine module 906
decides to
use a downlink RCC value that is different than the downlink RCC value sent by
the
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wireless device 1042, then the second transmit module 909 will indicate this
to the
wireless device 1042 by including the determined downlink RCC value in the
first
downlink message 204. The third transmit module 910 is configured to transmit
subsequent downlink messages 205 to the wireless device 1042 based on the
determined downlink RCC value (see FIGURE 2's step 7). The second determine
module 912 is configured to determine e.g., through the assistance of ACK/NACK
or
Measurement Report information supplied by the wireless device 1042 that a new
downlink RCC value should be used for the wireless device 1042 (see FIGURE 2's
step 8). The fourth transmit module 914 is configured to transmit the new
downlink
RCC value (number of repeated transmissions) to the wireless device 1042 (see
FIGURE 2's step 9). The number of repeated transmissions used by the RAN node
1022 to transmit the message which contains the new downlink RCC value is
determined using the downlink RCC value it has stored for the wireless device
1042
prior to deciding to use a new downlink RCC value.
The estimate module 916 is configured upon receipt of the message 202 (e.g.,
Channel Request message 202) to estimate an uplink RCC value for the wireless
device 1042 based on a quality (e.g., RSSI) of the received message 202 (see
FIGURE
4's step 2 and graph "A"). The add module 918 is configured to add (insert,
include)
the estimated uplink RCC value to the message 204 (e.g., Immediate Assignment
message 204) that is transmitted to the one wireless device 1042 (see FIGURE
4's step
3). The second receive module 920 is configured to receive from the wireless
device
1042 at least one uplink message 206 that has the number of repeated uplink
transmissions which corresponds to the uplink RCC value sent in message 204
(see
FIGURE 4's step 5). The fifth transmit module 922 is configured to transmit a
new
uplink RCC value if needed to the wireless device 1042 (see FIGURE 4's step
6).
The store module 924 is configured to store the RCC values applicable to both
the
uplink and downlink along with a TLLI or other local relevant identifier of
the
wireless device 1042 (see FIGURE 4's step 7). The sixth transmit module 926 is
configured to transmit the RCC values applicable to both the uplink and
downlink to
the CN node 107 along with a TLLI or other local relevant identifier of the
wireless
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device 1042 upon the termination of the connection between the wireless device
1042
and the RAN node 1022 (see FIGURE 4's step 8).
The third receive module 928 is configured to receive from the CN node 107
the paging message 208 with the RCC values for uplink and downlink for the
wireless device 1042 when a downlink payload becomes available for the
wireless
device 1042 (see FIGURE 5's step 1). The use module 930a is configured to use
the
received downlink RCC value to determine the paging repetition number for the
paging message 208' which is to be transmitted to the wireless device 1042
(see
FIGURE 5's step 2). The seventh transmit module 932a is configured to transmit
the
paging message 208' (which includes the uplink RCC value) using the determined
paging repetition number to the wireless device 1042 (see FIGURE 5's step 3).
The
fourth receive module 934a is configured to receive from the wireless device
1042 the
page response 210 having a number of repeated uplink transmissions based on
the
uplink RCC value in the paging message 208' (see FIGURE 5's step 5). As an
alternative to modules 930a, 932a and 934a, the RAN node 1022 includes the
third
determine module 930b which is configured to determine that the RCC values for
the
uplink and downlink received from the CN node 107 are outdated, then the
eighth
transmit module 932b is configured to transmit the paging message 208' a
repeated a
maximum number of times to the wireless device 1042, where the paging message
208' may include an uplink RCC value set to the highest RCC value (i.e., a
maximum number of repetitions) (see FIGURE 5's note 1). The fifth receive
module
934b is configured to receive from the wireless device 1042 the page response
210
having a highest number of repeated uplink transmissions based on the highest
uplink
RCC value.
As those skilled in the art will appreciate, the above-described modules 902,
904, 906, 908, 909, 910, 912, 914, 916, 918, 920, 922, 924, 926, 928, 930a,
930b,
932a, 932b, 934a, and 934b of the RAN node 1022 may be implemented separately
as
suitable dedicated circuits. Further, the modules 902, 904, 906, 908, 909,
910, 912,
914, 916, 918, 920, 922, 924, 926, 928, 930a, 930b, 932a, 932b, 934a, and 934b
can
also be implemented using any number of dedicated circuits through functional
combination or separation. In some embodiments, the modules 902, 904, 906,
908,
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909, 910, 912, 914, 916, 918, 920, 922, 924, 926, 928, 930a, 930b, 932a, 932b,
934a,
and 934b may be even combined in a single application specific integrated
circuit
(ASIC). As an alternative software-based implementation, the RAN node 1022 may
comprise a memory 1342, a processor 1322 (including but not limited to a
microprocessor, a microcontroller or a Digital Signal Processor (DSP), etc.)
and a
transceiver 1222. The memory 1342 stores machine-readable program code
executable
by the processor 1322 to cause the RAN node 1022 to perform the steps of above-
described method 800.
Referring to FIGURE 10, there is a flowchart of a method 1000 implemented in
a CN node 107 in accordance with an embodiment of the present disclosure. At
step
1002, the CN node 107 receives the RCC values for both the uplink and downlink
from either or both of the wireless device 1042 and the RAN node 1022 after
the
termination of the connection between the wireless device 1042 and the RAN
node
1022 (see FIGURE 4's steps 8 and 10). At step 1004, the CN node 107 stores the
downlink RCC value and the uplink RCC value associated with the one wireless
device. At step 1006, the CN node 107 transmits to the RAN node 1022 the
paging
message 208 with the RCC values for uplink and downlink for the wireless
device
1042 when a downlink payload becomes available for the wireless device 1042
(see
FIGURE 5's step 1). The RCC values for both uplink and downlink may be sent
together in the paging message 208 with a time stamp indicating the time that
the
RCC values had been uploaded to the CN node 1022 and cell identifier
information
about the cell where the wireless device 1042 was connected when these RCC
values
were obtained. This information and if desired additional information may also
be
provided in the paging message 208 to enable the RAN node 1022 to assess the
reliability of the downlink and uplink RCC values.
Referring to FIGURE 11, there is a block diagram illustrating structures of an
exemplary CN node 107 configured to interact with the wireless device 1042 and
the
RAN node 1022 in accordance with an embodiment of the present disclosure. In
an
embodiment, the CN node 107 may comprise a receive module 1102, a store module
1104, and a transmit module 1106. The receive module 1102 is configured to
receive
the RCC values for both the uplink and downlink from either or both of the
wireless
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device 1042 and the RAN node 1022 after the termination of the connection
between
the wireless device 1042 and the RAN node 1022 (see FIGURE 4's steps 8 and
10).
The store module 1104 is configured to store the downlink RCC value and the
uplink
RCC value associated with the one wireless device. The transmit module 1104 is
configured to transmit to the RAN node 1022 the paging message 208 with the
RCC
values for uplink and downlink for the wireless device 1042 when a downlink
payload becomes available for the wireless device 1042 (see FIGURE 5's step
1).
The RCC values for both uplink and downlink may be sent together in the paging
message 208 with a time stamp indicating the time that the RCC values had been
uploaded to the CN node 1022 and cell identifier information about the cell
where the
wireless device 1042 was connected when these RCC values were obtained. This
information and if desired additional information may also be provided in the
paging
message 208 to enable the RAN node 1022 to assess the reliability of the
downlink
and uplink RCC values.
As those skilled in the art will appreciate, the above-described modules 1102,
1104 and 1106 of the CN node 107 may be implemented separately as suitable
dedicated circuits. Further, the modules 1102, 1104 and 1106 can also be
implemented
using any number of dedicated circuits through functional combination or
separation. In
some embodiments, the modules 1102, 1104 and 1106 may be even combined in a
single application specific integrated circuit (ASIC). As an alternative
software-based
implementation, the CN node may comprise a memory 148, a processor 146
(including
but not limited to a microprocessor, a microcontroller or a Digital Signal
Processor
(DSP), etc.) and a transceiver 136. The memory 148 stores machine-readable
program
code executable by the processor 146 to cause the CN node 107 to perform the
steps of
the above-described method 1000.
EC-GSM Dynamic Coverage Class Update
At the aforementioned 3GPP TSG-GERAN Meeting #62, the Work Item
Description GP-140421, entitled "New Study Item on Cellular System Support for
Ultra Low Complexity and Low Throughput Internet of Things" was approved. One
of
the main objectives of this work item was to increase the coverage when
compared to
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existing GPRS services. The following description outlines a procedure that
ensures
that the CN node 107 (e.g., SGSN 107) always sends a paging message 208 to the
RAN
node 1022 (e.g., BSS 1022) indicating a downlink coverage class sufficient
(equal to or
higher than estimated by the wireless device 1042) for the RAN node 1022 to be
able to
5
successfully page the wireless device 1042. In particular, FIGURES 12-14
illustrate the
steps performed by the wireless device 1042, the RAN node 1022 and the CN node
107
to implement this new procedure (note: FIGURES 12, 13 and 14 are the same as
FIGURES 4, 6 and 10 but for the additional steps (see bold text) associated
with this
new procedure). Even though the discussion below is conducted in the scope of
an EC-
10 GSM (GSM
operation of packet data channels supporting extended coverage when
compared to legacy GSM network operation), the solutions described herein are
applicable to other types of wireless communication systems, including, for
example,
WCDMA, LTE, and WiMAX systems.
1. Determination of paging group
15 When paging
an EC-GSM wireless device 1042, in order to determine the specific
set of EC-PCH blocks to use to send the page message 208', the RAN node 1022
(e.g.,
BSS 1022) first needs to know:
= the eDRX cycle
= the downlink coverage class (DL CC), and,
20 = the IMSI of the wireless device 1042.
The downlink CC (downlink RCC value) is estimated by the wireless device 1042
and communicated to the network 100 (CN node 107). Thereafter, the RAN node
1022
receives the downlink CC (downlink RCC value) from the CN node 107 and uses it
to
determine the number of paging resources (EC-PCH blocks) that are required to
be sent
25 when
sending the paging message 208' to the wireless device 1042 in order for the
network 100 to identify the location of the wireless device 1042.
Even though the EC-GSM device 1042 is expected to provide the CN node 107
(e.g., SGSN 107) with their estimated DL CC (downlink RCC value) within, for
example, the context of the RAU procedure, there remains the possibility that
the
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wireless device 1042 will change their estimated DL CC (downlink RCC value) at
any
time between any two such successive procedures (see FIGURE 12's step 11 and
FIGURE 13's step 1302). This change in DL CC is discussed in more detail
below.
2. Methods for Updating DL coverage class
2.1 Pre-Paging Group Update of DL CC
Whenever the coverage class of the wireless device 1042 has deteriorated such
that it will not be able to decode the paging message 208' using the DL
coverage class
(downlink RCC value) last provided to the CN node 107 (e.g., SGSN 107) it is
proposed to use a Cell update procedure which requires the transmission of
only a
single RLC data block with the new downlink RCC value and is therefore a power
efficient way of triggering a DL CC update in the CN node 107 (e.g., SGSN 107)
(see
FIGURE 12's step 12, FIGURE 13's step 1304 and FIGURE 14's step 1402).
Furthermore, to reduce the possibility of excessive signaling between the
wireless
device 1042 and the CN node 107 (e.g., SGSN 107). the wireless device 1042 can
wait
until shortly before (e.g. 5 seconds) the next occurrence of its nominal
paging group
(i.e., based on its current DL CC) before performing a cell update to convey
its new DL
CC (downlink RCC value) to the CN node 107 (e.g., SGSN 107) (see FIGURE 12's
step 12, FIGURE 13's step 1304 and FIGURE 14's step 1402).
In addition, having the wireless device 1042 wait until just before the next
occurrence of its nominal paging group to finally decide that its DL CC needs
to be
changed ensures that the cell update will be used as sparingly as possible.
This solution
is used whenever the wireless device 1042 changes to a higher coverage class
(requiring
more blind repetitions) in order for the wireless device 1042 to be able to
(to a high
degree of probability) read a paging message 208' that may be sent using its
nominal
paging group. This does not guarantee that the wireless device 1042 will
always be able
to read a paging message 208' sent using the nominal paging group indicated by
its
recently transmitted cell update but will reduce the probability of missing a
paging
message 208' to the point where secondary paging mechanisms are not seen as
being
necessary.
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2.2 Transaction Time Update of DL CC
Whenever the DL coverage class (downlink RCC value) has improved such that
the EC-GSM device 1042 will be able to decode the paging message 208' using a
smaller number of repetitions there is in principal no need to update the DL
coverage
class with the CN node 107 (e.g., SGSN 107) just prior to the paging unless
there is a
need to saving paging bandwidth. In this case, the wireless device 1042 can
wait until
the next uplink transaction to inform the CN node 107 (e.g., SGSN 107) of the
new DL
CC instead of performing a cell update shortly before its next nominal paging
group as
described earlier. This is possible because the wireless device 1042 can
safely continue
to use its current DL CC (downlink RCC value) to read paging messages 208'
since the
wireless device 1042 is currently in a better coverage class than what the CN
node 107
(e.g., SGSN 107) currently assumes.
The most straight forward way for the wireless device 1042 to provide the CN
node
107 (e.g., SGSN 107) with the new DL coverage class (downlink RCC value) is to
modify the UL-UNITDATA PDU which transfers a wireless device's LLC-PDU and
its associated radio interface information across the Gb-interface. This
realization is
possible since whenever an EC-GSM device 1042 accesses the network 100 it
sends a
RACH request 202 (e.g., Channel Request message 202) to the RAN node 1022
(e.g.,
BSS 1022) including an indication of its estimated DL CC (downlink RCC value)
in
order for the RAN node 1022 (e.g., BSS 1022) to be able to properly assign
resources as
well as send the Immediate Assignment message 204 with the appropriate number
of
repetitions (see FIGURE 2's steps 4 and 7). This means that whenever an EC-GSM
wireless device 1042 sends uplink data the RAN node 1022 (e.g., BSS 1022) it
may add
the latest coverage class information to the UL-UNITDATA PDU it sends to the
CN
node 107 (e.g., SGSN 107) (see FIGURE 12's step 12, FIGURE 13's step 1304 and
FIGURE 14's step 1402).
3. Conclusions
To ensure that the CN node 107 (e.g., SGSN 107) always sends a paging message
208 to the RAN node 1022 (e.g., BSS 1022) indicating a downlink coverage class
(downlink RCC value) sufficient (equal to or higher) for the RAN node 1022
(e.g., BSS
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1022) to be able to successfully page the wireless device 1042 in extended
coverage
adaptations can be made as discussed above to both the Pre-Paging Group Update
of
the downlink coverage class and the transaction time update downlink
solutions.
In view of the foregoing, this disclosure provides a new mechanism for
enhancing the radio coverage based on the exchange of uplink and downlink
radio
condition information, referred to as Radio Coverage Category (RCC), between
the
wireless device 1042 (for example) and the network 100 for use in data
transmission
(e.g., control plane related signaling or user plane related payload
transmission). The
disclosed techniques are based on an exchange of estimated RCC values between
the
network 100 and the wireless device 1042 that are used to apply a number
(e.g., a pre-
defined number) of repeated transmissions on the radio interface. The RCC
value may
be estimated for the downlink (e.g., from the wireless device 1042
perspective) and
for the uplink (e.g., from the network 100 perspective). The RCC values may be
stored in the relevant network nodes 1022 and 107 (for example) and in the
wireless
device 1042 for use in determining the appropriate number of repeated
transmissions
for subsequent data transmissions, for example, at paging occasions. Some of
the
aspects of this disclosure that have been described herein include:
= An initial deployment and power on scenario wherein a wireless device
1042 (for example) uses its evaluation of downlink radio conditions or pre-
configured
information to determine the number of repeated transmissions the wireless
device
1042 should use when sending its very first Channel Request message 202 on the
RACH.
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= The use of a Channel Request message 202 (RRC Connection Request or
any control plane or user plane message transmission on the uplink) to
indicate an
RCC value that the wireless device 1042 has determined to be applicable for
subsequent message transmissions to that wireless device 1042 (e.g., AGCH or
PDTCH). The RCC value used by the RAN node 1022 (for example) for downlink
transmissions may be the RCC value last received from the wireless device
1042, an
estimated RCC value (e.g., based on uplink radio conditions), or a running
average of
received and/or estimated RCC values. The particular algorithm used for
determining
the used downlink RCC value may be implementation dependent. The downlink
RCC value may represent different numbers of repetitions depending on the
logical
channel or Radio Bearer used.
= The use of an Assignment message 204 or any control plane or user plane
message transmission on the downlink sent to a given wireless device 1042 (for
example) to indicate an RCC value that the RAN node 1022 (for example) has
determined to be applicable for subsequent uplink message transmissions (e.g.,
RACH or PDTCH) made by that wireless device 1042. This RCC value may
represent different numbers of repetitions depending on the logical channel
used. The
RCC value used for determining the number of repeated transmissions on the
uplink
may be based on the latest estimated uplink RCC value received from the
network
100, the wireless device's estimates of the uplink RCC value (e.g., based on
downlink
radio quality), or a running average of received and/or wireless device's
estimated
uplink RCC values.
The techniques disclosed herein have many advantages some of which are as
follows:
= Allows for a reduction in the amount of data transmission between the
RAN node and the wireless device.
= Reduces the wireless device's energy consumption and therefore
improves the battery lifetime.
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= Improves the reliability of the data delivery.
= Reduces the interference level in the network.
= Increases system capacity.
= Since many of the wireless devices used for MTC are expected to be
5 stationary, the disclosed techniques of RCC value estimation and
communication
between wireless devices and the network may be effective in ensuring
efficient
utilization of radio resources while still allowing for the possibility of
modifying the
applicable RCC values, if this ever becomes needed.
10 Those skilled in the art will appreciate that the use of the term
"exemplary" is
used herein to mean "illustrative," or "serving as an example," and is not
intended to
imply that a particular embodiment is preferred over another or that a
particular
feature is essential. Likewise, the terms "first" and "second," and similar
terms, are
used simply to distinguish one particular instance of an item or feature from
another,
15 and do not indicate a particular order or arrangement, unless the
context clearly
indicates otherwise. Further, the term "step," as used herein, is meant to be
synonymous with "operation" or "action." Any description herein of a sequence
of
steps does not imply that these operations must be carried out in a particular
order, or
even that these operations are carried out in any order at all, unless the
context or the
20 details of the described operation clearly indicates otherwise.
Of course, the present disclosure may be carried out in other specific ways
than those herein set forth without departing from the scope and essential
characteristics of the invention. One or more of the specific processes
discussed
above may be carried out in a cellular phone or other communications
transceiver
25 comprising one or more appropriately configured processing circuits,
which may in
some embodiments be embodied in one or more application-specific integrated
circuits (ASICs). In some embodiments, these processing circuits may comprise
one
or more microprocessors, microcontrollers, and/or digital signal processors
programmed with appropriate software and/or firmware to carry out one or more
of
CA 02953294 2016-12-21
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41
the operations described above, or variants thereof. In some embodiments,
these
processing circuits may comprise customized hardware to carry out one or more
of
the functions described above. The present embodiments are, therefore, to be
considered in all respects as illustrative and not restrictive.
Although multiple embodiments of the present disclosure have been illustrated
in the accompanying Drawings and described in the foregoing Detailed
Description, it
should be understood that the invention is not limited to the disclosed
embodiments, but
instead is also capable of numerous rearrangements, modifications and
substitutions
without departing from the present disclosure that as has been set forth and
defined
within the following claims.
